The invention relates to human interface devices and specifically to the connection of a user personal control unit (PCU) to a controlling seat electronics box (SEB) used on an in-flight entertainment (IFE) system of an aircraft or an in-travel system of a vehicle. Specifically, this invention relates to the data transport mechanism and associated cabling that interfaces between the human interface device and the SEB.
An in-flight entertainment (IFE) system (this term, as used herein, applies to any in-transit vehicle entertainment system), usually comprises a server or series of servers located in a common, centralized location on an aircraft that is capable of distributing multimedia content, and real-time interactive data (games) to passengers. In these systems, it is common for the passenger to be provided with a passenger system having a video display unit (VDU) with a video interface, an audio interface, and a personal control unit (PCU) that can be used to interact with the passenger system.
These systems and associated interfaces require sophisticated electronics for data delivery between the IFE and the passenger system. Often the communications link will comprise an area distribution network (ADN) that handles the transmission of communications targeted to or originating from a particular area of the aircraft to a central computer.
For data that is ultimately targeted to or sent from the passenger system, it is not unusual to have a substantial amount of electronic equipment that is required to handle tasks such as decoding audio and video information, handling game control information, and the like. Unfortunately, the area in which the passenger sits is often crowded, and therefore it is advantageous to have the necessary electronics located away from the seat, but minimally so, in a seat electronics box (SEB).
The SEB can be located in an area near a passenger seat, yet far enough away so that it does not take up valuable room within the seating area of the passenger. Although for certain purposes it is desirable to locate the SEB as close to the passenger seat as possible, for other purposes, it may be desirable to locate the SEB further away. For example, it may be practical because of cost, weight, or space savings, to use a quad seat electronics box (QSEB) that is capable of serving four passenger entertainment systems. Thus, the SEB may be located further away from the passenger entertainment system than is desirable to achieve certain goals.
One of the components of information handled by the SEB is the information generated by PCU of the user. The PCU is often, but not necessarily, a handheld unit. This PCU permits the passenger to control various aspects of the entertainment system, such as channel or video-on-demand selection, provide input for video games, etc.
It is desirable to use standard communications protocols for communicating information to and from the PCU, and one such standard is the Universal Serial Bus (USB) standard. It is thus advantageous to utilize the USB standard for communicating information from the PCU to the SEB.
One problem with the current systems is that USB cables that are used between the SEB and the PCU are limited to five meters due to the constraints of USB technology. Although communications problems due to long-run cabling can be addressed by limiting disconnects (connectors) and using high quality cables to some small degree, this does not alleviate the problem of communication reliability.
The use of USB repeaters for extending the reach of USB devices is known. However, these known USB repeaters are generally somewhat large and heavy and do not have a great deal of robustness and reliability, particularly for achieving the size and weight constraints, robustness and reliability as required by the aerospace regulations, and are not capable of accommodating other signals.
What is needed is a reliable mechanism that conforms to aerospace regulations, and that allows for extending the range of devices connected via USB and is adapted for the aircraft or vehicle environment. Specifically, it is desirable to maximize customer satisfaction when they are using their PCU device to control the IFE system while at the same time addressing the concerns of the vehicle owners in minimizing costs associated with weight, etc.